Gas sensor

A method for measurement of nitrogen oxides using a gas sensor. To reliably measure nitrogen oxides, the sensor has a reference electrode representing a constant oxygen partial pressure, at least two electrode pairs, with common a electrode associated with each pair of electrodes, and solid electrolytes arranged between the two electrodes of an electrode pair directly at the electrodes. The solid electrolyte between a first electrode pair is gas-permeable, while the solid electrolyte between a second electrode pair is gastight, whereby the second electrode pair is adapated for potentiometric or amperometric measurement of nitrogen oxides, and the first electrode pair is adapted for application of a current or a voltage to pump oxygen. The second electrode of the second electrode pair is constructed as a reference electrode on the reference gas side of the solid electrolyte of the second electrode pair. The sensor also has electrical leads for connection and for take-away of electric measurement signals.